I like to redirect the swing rope through the crown of a tree to distribute load. I anchor at the base of the tree or a second tree. Right now I'm using a Grigri as a swing height adjuster. When the swing is in operation I lock off the Grigri with an overhand on a bight tied just above the Grigri. A Prusik Hitch would work just as well if not better, I'm testing different options. I put a Dan House conduit rope sleeve where each redirect contacts the tree.
I'm using Sterling HTP 10mm as my swing line, stretch is an issue so the HTP is good, very low stretch. With multiple redirects the overall strength and safety of the system is very good but that means there's give in the system so easy height adjustment for kids vs. adults for example is important.
This type of setup is very high performance, if the rope is hung high the rider can develop a huge swing and velocity compared to a classic yard swing. Must be really careful introducing people to a swing like that so they don't hurt themselves. Small steps, hold tight
Some video from my current swing setup, I'll post some more detailed setup photos:
-AJ